This invention relates generally to devices for monitoring the passage of objects across a perimeter line, and in particular to a perimeter monitoring device for use with a radiation imaging system to detect passage of objects across a perimeter line around a cordoned area in which the imaging device is located.
It is necessary to restrict access to the area around certain types of equipment while it is in operation in order to prevent injury or disruption of the operation of the equipment. One example of such type of equipment is radiation imaging equipment, such as is used for medical imaging procedures. Restricting access to the equipment is necessary to prevent physical injury that may result from being struck by movable equipment of the imaging system, such as gantry arms, on which components of the imaging system are mounted.
It is thus desirable to have a perimeter sensing system that can monitor passage of objects (such as people) across a perimeter line surrounding a cordoned area in which the imaging machine is disposed. Such a sensing system is beneficially remote (that is, does not require a human operator in the immediate vicinity) and a system on which the radiation does not have an adverse effect.